


Baptism of Fire

by NamelesslyNightlock, Rabentochter



Series: Veni, Vedi, Witcher [5]
Category: Marvel Cinematic Universe, The Avengers (Marvel Movies), The Witcher (TV)
Genre: Admiration, Alternate Universe - The Witcher Fusion, Angst, Blood, Curiosity, Feels, Fights, Fire, Gen, Hopeful Ending, Humanity, Injured Loki (Marvel), Loki (Marvel) Does What He Wants, MerMay, Merman Loki (Marvel), Moral Dilemmas, Pre-Slash, Swords, Tony Stark Does What He Wants, Tony Stark Has A Heart, Violence, Witcher Tony Stark
Language: English
Status: Completed
Published: 2020-05-05
Updated: 2020-05-05
Packaged: 2021-03-03 04:41:15
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,940
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24019171
Author URL: https://archiveofourown.org/users/NamelesslyNightlock/pseuds/NamelesslyNightlock, https://archiveofourown.org/users/Rabentochter/pseuds/Rabentochter
Summary: Tony is a Witcher, and he knows a monster when he sees one.Or at least… he thinks he does.
Relationships: Loki/Tony Stark
Series: Veni, Vedi, Witcher [5]
Series URL: https://archiveofourown.org/series/1588387
Comments: 18
Kudos: 196





	Baptism of Fire

**Author's Note:**

> Another Witcher AU, this one in the spirit (kind of, anyway) of MerMay!  
>   
> Art by **Rabentochter** , fic by **NamelesslyNightlock.**

Monsters are _monsters_.

That was one thing that had been drilled into Tony’s head during his training, during every moment at Kaer Morhen. No matter what they looked like, how big they were or how many teeth they had– if the creature was monster, then it needed to be killed.

But, the mantra wasn’t there only to keep the Witchers on track in their mission to kill the creatures of the night– it was also there to remind them that it wasn’t their job to kill creatures who _weren’t._

Elves, dragons, humans– they were not monsters, and so Witchers did not kill them. Not unless it was self-defence, anyway.

But… merfolk?

Holy fuck, but this thing was _definitely_ a monster.

Tony had never fought anything quite so _fierce_ before. It was like it was possessed by a devil, like killing Tony was its one, single purpose in life. He’d taken the job from the governor of the nearby port, which had lived in fear of this creature for months. The mer had been dragging people – and entire _boats –_ down to the crushing depths of the ocean before swimming away, leaving anyone who dared to sail bloody and bitten with cold, half drowned and half _dead._

The mer’s head was worth a pretty penny, as the people were desperate—

And Tony? Pft, he thought he had this in the bag. He’d killed the worst of the worst– strigas, archespores, and selkiemores, along with near on anything else anyone could care to name. How hard could be to kill a single mer?

Well.

As it turned out.

It was pretty fucking _hard_.

Tony’d been fighting for about an hour. He’d managed to draw it into the shallows, had set the bay ablaze with oil to keep it there– but that hadn’t seemed to make anything _easier._ The flames licking up into the sky only made the creature mad, and its fangs snapped and snarled as it lashed out with its claws. Tony already had one deep gash in his calf, and another along his thigh– the salt water around him was stained with red, and he knew that he needed to finish this quickly or he would risk tiring.

But the damn thing would not stay _still—_

Tony could stab into the water with his silver sword as much as he wished, but the bloody thing shot away with a hard swipe of its tail—

One of the spines along the tail caught on Tony’s leg, causing him to snarl in pain as it tore across his skin _again_. He knew that he couldn’t continue on this way, he needed something _more_. So, keeping his eye on the ripple across the surface, the only indication he had of the mer’s presence, he reached into a pouch and withdrew a small vial of potion, pulled the cork between his teeth, and downed it in a single gulp—

Then the power of the magic contained in the liquid burned through his veins, staining dark lines around his eyes as they turned from amber to purest onyx. The potion would give him speed, strength– and an enhancement of his _sight._

The monster was still difficult to see, its dark, murky green scales blending perfectly with the colour of the night-time sea, its pale, almost-green skin barely more than a flicker of moonlight across the surface of the water. But… it was more than Tony’d had before– and combined with sun that was just starting to peak over the horizon, it was more than enough.

Sword in hand, silver gleaming orange in the light of the blazing fire and the rising sun, Tony began to make his way close to the heat of the flames, into deeper water that he had previously tried to avoid. He needed the mer to come closer, needed to let it think that it had _won._

His lips curled as he saw the movement, that strong, deadly tail cutting through the water, pale green arms reaching out, black claws curled at the ready—

Then Tony stabbed down into the waved, and _missed_ – but as the mer tried to dart to the side, Tony kicked out with his booted foot as hard as he could.

He heard the inhuman screech even though the water. Tony stepped forward, and the injured mer swam back, moving more slowly now. Through the disturbed sea’s surface Tony could see eyes that glowed red, fangs that bared in preparation for blood. But its arms were wrapped around its middle, protecting its chest where Tony had managed to land his kick. It rolled out of the way as Tony stabbed with his sword once again—

And it rolled right into the path of the knife in Tony’s other hand.

The knife wasn’t silver, and it wouldn’t be enough to kill the mer– but it was _certainly_ enough to pin him down. And as the blade pierced right through the mer’s tail fin and hit the rocky bed below, the mer writhed and _screamed_ , blood seeping around the knife and staining the water a deep, _monstrous_ blue.

Tony adjusted his grip on the hilt of his sword, holding it with two hands as he prepared to plunge it into the monster’s heart. Red eyes glared up at him, vicious to the very last—

And then the mer _tore_ its fin from the knife, ripping through its own flesh. Blue blood blossomed through the shallows as it twisted away from Tony, and Tony just… stared, for a moment, hardly believing it would disfigure itself in such a way—

It wasn’t often that a creature would even think to cause itself such pain when trapped, and Tony almost couldn’t fathom why this one would do it.

Not that it mattered, really. The flames were still burning hot, making the water far too warm for the cold-blooded mer to be able to swim through– so there was only one way for the monster to go.

Tony followed at his leisure as the mer struggled toward the shallows, its torn fin looking a torture, its movements jerked and stilted. As it drew closer to the bank, it was forced to drag itself along the ground, claws digging into the sand, chest and tail scratching across the gritty mixture of shells and rock.

It just refused to give up, and as Tony waded through the water to stand beside the writhing monster, it even looked up at him with something that almost seemed like… defiance.

Surely not, though. That would mean that it had some level of sentient thought, that this creature was—

“If you are going to kill me, then do get on with it,” the monster snapped, the words hissed past its sharp fangs—

But that was—

That was _impossible._

“You didn’t just talk,” Tony snapped, shifting his sword a little. “Monsters don’t _talk—”_

“Then perhaps I am not a monster, _Witcher,”_ the mer spat. “Perhaps I am no more a monster than _you.”_

No.

_No._

_A monster is a monster._

Tony bared his teeth and raised his sword, elbows bent sharp as he prepared to slam it into the mer’s heart.

This creature had hurt people. This creature was a monster.

It had to be.

But…

What if… it wasn’t?

What if the mer was right?

What if mers, like other inhuman creatures Tony had encountered, were no more a monster than Witchers?

Elves were not human, but nor were they monsters. Dragons… they had wings, scales, fangs and claws, appearing even less humanoid than this mer, and yet they were _civilised_ and _protected_ by the Witchers.

So… perhaps it was possible…

But, no. Elves, dragons, even Witchers like Tony, they all bled _red._ But the blood that was seeping into the water was _blue_ —

And yet… the mer was talking. The mer was _waiting,_ waiting for Tony to make a decision. Though all the while those bright red eyes were shifting around, looking for a weakness no doubt, _still_ trying to get away with a desperate kind of hope for survival despite the odds stacked against its favour.

And that desperation… it was _so_ human.

Tony pressed his lips together, and relaxed his arm– though he did not yet sheath his sword.

The mer’s eyes widened slightly, as if it couldn’t believe what it was seeing– and Tony took the opportunity presented by his surprise to say his bit.

“You’ve hurt people,” he said. “You’ve caused a hell of a lot of pain and destruction.”

The mer bared its fangs, eyes narrowed once more, and Tony growled in return.

“It’s only because you haven’t _killed_ anyone that I’m even considering this, but if this goes on—”

“They keep coming into my sea, searching for me,” the creature snapped. “I won’t sit defenceless.”

“I’ll tell them you’re dead, then,” Tony said. The mer had left about half of one its fins back there, that would do well enough for proof. “And you _leave them alone.”_

The mer seemed to consider that for a moment– and it was the clear intelligence behind those red eyes that well and truly settled the matter for Tony.

This creature might be incredibly dangerous, but he wasn’t the kind of monster that Tony killed.

He stepped back, needing to ask one more thing. One more test. “Tell me,” Tony said. “Have you got a name?”

“I do,” the mer said, the suspicion, fear, and hate still plain on his face. “But I won’t tell it to you, not if you’re planning on _using_ it—”

“Where did you learn to speak a human language?” Tony cut in, not taking too kindly to being compared to a _fae._

“From the _humans_ ,” the creature snapped in reply. “If this is to go on any longer, I would almost rather you kill me—”

“I’m not going to do that.” To emphasise his point, Tony finally sheathed his weapons. He would need to properly clean them of salt later, blade and sheath both, but he knew it would put the mer more at ease.

And the mer did seem further surprised by that, even as he immediately pulled his tail a little closer toward itself.

“Why not?” he snapped.

“Because _I_ am not a monster,” Tony replied. “And because you’re not, either. Or am I wrong?”

They held each other’s gaze for a moment longer, two creatures watching, waiting for the other to break the unspoken truce, the tension burning brighter than the slowly dwindling fire.

Then—

“My name is Loki,” the mer said– and although his tone was harsh… there was a curiosity in his gaze now that almost seemed to match Tony’s.

“Tony,” Tony replied. Then he moved to the side, the intention in the gesture clear.

As expected, the mer instantly made a lunge past him, his damaged tail still more than able to propel him through the water. But then, just before ducking under the surface entirely, Loki turned to meet Tony’s gaze once more.

“You… are not what I expected,” he said.

And then, with one final flick of his bloodied tail, Loki vanished beneath the waves.

Tony watched after him, not yet making a move to get out of the water. He watched that dark shape – visible now that the sun was almost up – approach the now broken line of fire before shooting through a gap.

He couldn’t help but think that the mer – _Loki_ – certainly hadn’t been what Tony was expecting either.

And as he stepped out of the ocean, his sodden boots crunching on the cold, early morning sand– he couldn’t help but feel sure that this would not be their last meeting.

**Author's Note:**

> The art for this fic is on tumblr [here.](https://rabentochter.tumblr.com/post/617271292436021248/baptism-of-fire-another-witcher-au-for-starved)


End file.
